On weight lifting equipment. I know it is a three letter abbreviation but I can't remember what its called n can't find on google. Its the real tuff plastic that protects parts of the metal.
Can you be a bit more specific; what part of the equipment do you mean? Thinking of various parts now, and there various types of plastics used.
ABS. Derlin will also work.
ABS is still a bit brittle, though less than it's brother PS. Lego is made of ABS, for example, and those old CD cases were made of PS. They break very easily with just a little bit of force.
PVC?
PVC is though and a bit elastic (or non brittle) if enough plasticiser is added. Those rubbery Barbie dolls are/were made of PVC.